We compare multistability in central pattern generator (CPG) motifs comprised either of biologically plausible Hodgkin-Huxley models of bursting leech heart interneurons or of phenomenologically reduced phase models. We propose a novel computational tool for detailed examination of polyrhythmic bursting in biophysical CPG models with coupling asymmetries and arbitrary coupling strength. We carr...

The geometric structures of small cationic rhodium clusters Rh(n)(+) (n = 6-12) are investigated by comparison of experimental far-infrared multiple photon dissociation spectra with spectra calculated using density functional theory. The clusters are found to favor structures based on octahedral and tetrahedral motifs for most of the sizes considered, in contrast to previous theoretical predict...

Selenoproteins use the rare amino acid selenocysteine (Sec) to act as the first line of defense against oxidants, which are linked to aging, cancer, and neurodegenerative diseases. Many selenoproteins are oxidoreductases in which the reactive Sec is connected to a neighboring Cys and able to form a ring. These Sec-containing redox motifs govern much of the reactivity of selenoproteins. To study...

WebFR3D is the on-line version of 'Find RNA 3D' (FR3D), a program for annotating atomic-resolution RNA 3D structure files and searching them efficiently to locate and compare RNA 3D structural motifs. WebFR3D provides on-line access to the central features of FR3D, including geometric and symbolic search modes, without need for installing programs or downloading and maintaining 3D structure dat...

Spanish architect Antoni Gaudı́ drew on natural precedent to create fantastic organically inspired designs. This paper examines some common motifs in his works, and demonstrates how simple geometric operations can be applied to polyhedral models to achieve similar results. The importance of the partial hyperbolic paraboloid surface (or hypar) is discussed in this context. r 2007 Elsevier Ltd. Al...

We introduce a new methodology for the analysis of heart interbeat interval time series based on the geometric/topological analysis of spaces of frequently occurring motifs (short patterns in the data). We use these methods to identify interesting differential features in data from three patient groups: healthy, congestive heart failure, and atrial fibrillation.